Interspinous process fixation devices, systems, instruments and methods of assembly and use

ABSTRACT

The present invention discloses spinous process fixation devices, systems, and instruments. The spinous process fixation device includes a first member, a second member, a third member, and a fourth member. Each of the first and second members includes a body and an engagement member and the engagement member of the first member couples to the engagement portion of the second member. Each of the third and fourth members also includes a body and an engagement member and the engagement member of the third member couples to the engagement portion of the fourth member. A method of assembling the spinous process fixation device and methods of using the spinous process fixation devices are also disclosed. A reamer instrument is also disclosed.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of PCT Application No.PCT/US2015/20520 filed on Mar. 13, 2015, which claims priority benefitunder 35 U.S.C. § 119(e) of U.S. provisional application No. 61/953,720filed Mar. 14, 2014, which is incorporated herein by reference in itsentirety.

FIELD OF THE INVENTION

The present invention relates generally to general surgery, orthopaedicand neurosurgical implants used for insertion within a patient's spine.More specifically, but not exclusively, the present invention concernsinterspinous process fixation devices and systems implanted in the spinefor spinal stabilization.

BACKGROUND OF THE INVENTION

Many currently available stabilization devices and methods for thethoracic and lumbar spine require open surgery. During open surgeryextensive dissection of the paraspinous musculature and ligamentousattachments from the spinous processes is performed which results inadditional risks and recovery time.

Thus, new devices, systems, and methods are needed that reduce oreliminate the extensive dissection of the paraspinous musculature andligamentous attachments from the spinous processes.

SUMMARY OF THE INVENTION

Aspects of the present invention provide interspinous process fixationdevices, systems, instruments, and methods of assembly and use that canmaintain or re-establish anatomic spacing of the spinous processeswithin a patient's spine.

In one aspect, provided herein is a spinous process fixation device,including a first attachment portion and a second attachment portionengaging the first attachment portion, wherein the first attachmentportion and the second attachment portion are positioned to couple atleast two spinous processes. The first attachment portion including afirst member and a second member configured to couple to the firstmember. The second attachment portion including a third member and afourth member configured to couple to the third member.

In another aspect, provided herein is a spinous process fixation system,including a spinous process fixation device and an insertion instrumentconfigured for engagement with the spinous process fixation device.

In yet another aspect, provided herein is a method of assembling aspinous process fixation device, including obtaining a first member anda second member. The method may also include coupling the first memberto the second member to form a first attachment portion. The methodfurther includes obtaining a third member and a fourth member. Inaddition, the method includes coupling the third member to the fourthmember to form a second attachment portion. Finally, the method includessecuring the second attachment portion to the first attachment portion.

In another aspect, provided herein is a method for using a spinousprocess fixation system including creating an incision in a patient overat least two spinous processes. The method may also include obtaining afirst member and a second member of a spinous process fixation deviceand engaging the first member and the second member with an insertioninstrument. The method may further include inserting the insertioninstrument with the first member and the second member into the incisionand aligning the first member and the second member with a firstinterspinous process. The method may include actuating the insertioninstrument to position the first and second members relative to thefirst interspinous process and removing the insertion instrument fromthe patient. Next, the method may include obtaining a third member and afourth member of the spinous process fixation device and engaging thethird member and the fourth member with the insertion instrument. Themethod may still further include inserting the insertion instrument withthe third member and fourth member into the incision and aligning thethird member and the fourth member with a second interspinous process.The method may also include actuating the insertion instrument toposition the third member and the fourth member relative to a secondinterspinous process and the third member and the fourth member relativeto the first member and the second member. Finally, the method mayinclude removing the insertion instrument and closing the patient.

In a further aspect, provided herein is a spinous process realignmentdevice, including a body, a first pair of moveable members engaged withthe body on a first side, and a second pair of moveable members engagedwith the body on a second side opposite the first side.

In still a further aspect, provided herein is a method of using aspinous process realignment device, including placing an incision overthe patient's spine and obtaining the spinous process realignmentdevice. The method may also include preparing the patient's spine forinsertion of the spinous process realignment device and inserting thespinous process realignment device into the patient's spine between twospinous processes. The method may further include aligning the spinousprocess realignment between the two spinous processes. The method mayinclude inserting an instrument into a first cavity of the interspinousprocess device and deploying at least one of a first set of moveablemembers to engage a first spinous process. In addition, the method mayalso include removing the instrument from the first cavity and insertingthe instrument into a second cavity of the interspinous process device.Next, the method may include deploying at least one of a second set ofmoveable members to engage a second spinous process. Then the method mayinclude removing the instrument from the patient and closing thepatient's incision.

In another aspect, provided herein is a reamer instrument, including afirst shaft, a second shaft with a reamer portion, and a joint rotatablycoupling the first shaft to the second shaft. The joint may include afirst body, a second body, and a hinge member for coupling the firstbody to the second body. The hinge member may include a first pin forrotatably engaging the first body and a second pin for rotatablyengaging the second body, wherein the first pin is coupled to the secondpin.

These, and other objects, features and advantages of this invention willbecome apparent from the following detailed description of the variousaspects of the invention taken in conjunction with the accompanyingdrawings.

BRIEF DESCRIPTION OF DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of the specification, illustrate embodiments of the invention andtogether with the detailed description herein, serve to explain theprinciples of the invention. The drawings are only for purposes ofillustrating preferred embodiments and are not to be construed aslimiting the invention. It is emphasized that, in accordance with thestandard practice in the industry, various features are not drawn toscale. In fact, the dimensions of the various features may bearbitrarily increased or reduced for clarity of discussion. Theforegoing and other objects, features and advantages of the inventionare apparent from the following detailed description taken inconjunction with the accompanying drawings in which

FIG. 1 is a perspective view of an embodiment of a spinous processrealignment device, in accordance with an aspect of the presentinvention;

FIG. 2 is a posterior view of the spinous process realignment device ofFIG. 1, in accordance with an aspect of the present invention;

FIG. 3 is a partially exploded perspective view of the spinous processrealignment device of FIG. 1, in accordance with an aspect of thepresent invention;

FIG. 4 is a partially exploded posterior view of the spinous processrealignment device of FIG. 1, in accordance with an aspect of thepresent invention;

FIG. 5 is an exploded perspective view of the spinous processrealignment device of FIG. 1, in accordance with an aspect of thepresent invention;

FIG. 6 is an exploded posterior view of the spinous process realignmentdevice of FIG. 1, in accordance with an aspect of the present invention;

FIG. 7 is a bottom view of an insertion instrument, in accordance withan aspect of the present invention;

FIG. 8 is an isometric view of the insertion instrument of FIG. 7engaging a first attachment portion of the spinous process realignmentdevice of FIG. 1 in an open position, in accordance with an aspect ofthe present invention;

FIG. 9 is an isometric view of the insertion instrument of FIG. 7engaging the first attachment portion of the spinous process realignmentdevice of FIG. 1 in a closed position, in accordance with an aspect ofthe present invention;

FIG. 10 is a posterior view of the patient's spine showing the firstattachment portion of the spinous process realignment device of FIG. 1implanted on the patient's spine, in accordance with an aspect of thepresent invention;

FIG. 11 is an isometric view of the insertion instrument of FIG. 7engaging the second attachment portion of the spinous processrealignment device of FIG. 1 in an open position and the firstattachment portion of the spinous process realignment device of FIG. 1in a closed position, in accordance with an aspect of the presentinvention;

FIG. 12 is an isometric view of the insertion instrument of FIG. 7engaging the second attachment portion of the spinous processrealignment device of FIG. 1 in a closed position engaging the firstattachment portion of the minimally invasive realignment device of FIG.1, in accordance with an aspect of the present invention;

FIG. 13 is a posterior view of the patient's spine showing the first andsecond attachment portions of the spinous process realignment device ofFIG. 1 implanted on the patient's spine, in accordance with an aspect ofthe present invention;

FIG. 14 is a posterior, lateral perspective view of the patient's spineshowing the spinous process realignment device of FIG. 1 implanted onthe patient's spine, in accordance with an aspect of the presentinvention;

FIG. 15 depicts one embodiment of a method of using a spinous processrealignment device, in accordance with an aspect of the presentinvention;

FIG. 16 is a partially exploded perspective view of another embodimentof an interspinous process device, in accordance with an aspect of thepresent invention;

FIG. 17 is a perspective view of the interspinous process device of FIG.16 with the moveable members deployed, in accordance with an aspect ofthe present invention;

FIG. 18 is an exploded perspective view of the interspinous processdevice of FIG. 16, in accordance with an aspect of the presentinvention;

FIG. 19 is a posterior, lateral perspective view of a patient's spineshowing the interspinous process device of FIG. 16 implanted in thepatient's spine, in accordance with an aspect of the present invention;

FIG. 20 is a perspective view of yet another embodiment of aninterspinous process device, in accordance with an aspect of the presentinvention;

FIG. 21 is a perspective view of the interspinous process device of FIG.20 with the moveable members deployed, in accordance with an aspect ofthe present invention;

FIG. 22 is an exploded perspective view of the interspinous processdevice of FIG. 20, in accordance with an aspect of the presentinvention;

FIG. 23 is a posterior, lateral perspective view of a patient's spineshowing the interspinous process device of FIG. 20 implanted in thepatient's spine, in accordance with an aspect of the present invention;

FIG. 24 is a side view of a worm gear mechanism of the interspinousprocess devices of FIGS. 16 and 20, in accordance with an aspect of thepresent invention;

FIG. 25 is a perspective view of a locking mechanism for engagement withthe worm gear mechanism of FIG. 24, in accordance with an aspect of thepresent invention;

FIG. 26 depicts one embodiment of a method of using an interspinousprocess device, in accordance with an aspect of the present invention;

FIG. 27 is a perspective view of a reamer instrument in a firstposition, in accordance with an aspect of the present invention; and

FIG. 28 is a perspective view of the reamer instrument of FIG. 27 in asecond position, in accordance with an aspect of the present invention.

DETAILED DESCRIPTION FOR CARRYING OUT THE INVENTION

Generally stated, disclosed herein are spinous process fixation devices,interspinous process devices, systems, and instruments. Further, methodsfor assembling and inserting the spinous process fixation devices andinterspinous process devices are discussed.

In this detailed description and the following claims, the wordsproximal, distal, anterior, posterior, medial, lateral, superior,inferior, cephalad and caudally are defined by their standard usage forindicating a particular part of a bone or implant according to therelative disposition of the natural bone or directional terms ofreference. For example, “proximal” means the portion of an implantnearest the insertion instrument, while “distal” indicates the portionof the implant farthest from the insertion instrument. As fordirectional terms, “anterior” is a direction towards the front side ofthe body, “posterior” means a direction towards the back side of thebody, “medial” means towards the midline of the body, “lateral” is adirection towards the sides or away from the midline of the body,“superior” means a direction above and “inferior” means a directionbelow another object or structure, “cephalad” means a direction towardthe head and “caudally” means a direction toward the inferior part ofthe body.

Referring to the drawings, wherein like reference numerals are used toindicate like or analogous components throughout the several views, andwith particular reference to FIGS. 1-6, there is illustrated anexemplary embodiment of a device 100. The terms “device,” “spinousprocess fixation device,” “minimally invasive realignment device,”“spinal column realignment device,” and “percutaneous interspinousprocess fixation device” may be used interchangeably herein as theyrefer to essentially the same device. The device 100 may be configuredto restrict painful motion while still allowing for normal motion of thespine by maintaining or stabilizing the spacing and alignment of thespinous processes within a patient's spine. The device 100 may be used,for example, for fusion of the lumbar spine, limited segment fusion ofthe thoracic spine, posterior stabilization of the anterior lumbarinterbody fusion, and for other areas where fusion of the spinousprocesses is desirable.

As shown in FIGS. 1-6, the device 100 may include a first member 110 anda second member 130. Further, the device 100 may include a third member150 and a fourth member 170. In the depicted embodiment, the firstmember 110 is configured to engage the second member 130 to form a firstattachment portion 190 and the third member 150 is configured to engagethe fourth member 170 to form a second attachment portion 192, as shownin FIGS. 3-4.

As shown in FIGS. 5 and 6, the first member 110 may include a body 112with an engagement portion or member 114 which may extend out from thebody 112, for example, in a relatively perpendicular direction. Theengagement portion 114 may include a plurality of teeth 116 on the sidesurfaces. The body 112 may also include a slot 118 on an exteriorsurface 113. The slot 118 may extend from a first side to a second sideon the exterior surface 113 near, for example, the bottom of the body112. In addition, the first member 110 may include at least oneengagement protrusion 120 on an interior surface 115 of the body 112, asshown in FIG. 6. The at least one engagement protrusion or protuberance120 may be positioned, for example as shown in the depicted embodiment,above the engagement portion 114 and toward the top of the body 112. Theat least one engagement protrusion 120 may include, for example, spikes,ridges, serrations, teeth, and other forms of coatings or textures thatproduce a rough surface for engaging with a spinous process to securethe first member 110 to the spinous process.

With continued reference to FIGS. 5 and 6, the second member 130 mayinclude a body 132 with an engagement portion or member 134 which mayextend away from the body 132, for example, in a generally perpendiculardirection. The engagement portion 134 may include a first engagementsegment 142 and a second engagement segment 144. The first and secondengagement segments 142, 144 may be positioned parallel to each otherand perpendicular to the long axis of the body 132 to create a channelsized to receive engagement portion 114. The engagement portion 134 mayalso include a plurality of teeth 136 positioned on the interiorsurfaces of the engagement portion 134. The plurality of teeth 136 maybe positioned on the inner surface of the first engagement segment 142and the inner surface of the second engagement segment 144. Theplurality of teeth 136 may also be configured to engage the plurality ofteeth 116 on the engagement portion 114 of the first member 110. Thebody 132 may also include a slot 138 on an exterior surface 133 whichextends between the first side and second side of the exterior surface133 near the bottom of the body 132. The second member 130 may alsoinclude at least one engagement protrusion or protuberance 140 on theinterior surface 135 of the body 132. The at least one engagementprotrusion 140 may be positioned on the interior surface 135 of the body132, for example, as shown in the depicted embodiments. The at least oneengagement protrusion 140 is positioned on one side of the engagementportion 134 and toward the end of the body 132. The at least oneengagement protrusion 140 is configured similar to engagement protrusion120.

Also shown in FIGS. 5 and 6, the third member 150 may include a body 152with an engagement portion or member 154. The engagement portion 154 mayextend away from the body 152, for example, in a relativelyperpendicular direction from the interior surface 155. The engagementportion 154 may include a plurality of teeth 156 on the side surfaces.The body 152 may also include a protrusion 158 on an interior surface155. The protrusion 158 may extend, for example, away from the body 152in a relatively perpendicular direction and may extend from the firstside to the second side of the interior surface 155 near the top of thebody 152. The protrusion 158 may be shaped and sized to engage thecorresponding slot 118 in the first member 110 or the slot 138 in thesecond member 130. As shown in FIG. 6, the third member 150 may alsoinclude at least one engagement protrusion or protuberance 160positioned on an interior surface 155 of the body 152. The at least oneengagement protrusion 160 may be positioned, for example, on one side ofthe engagement portion 154 and toward the end of the body 152. The atleast one engagement protrusion 160 is configured similar to engagementprotrusions 120, 140.

The fourth member 170 may include a body 172 with an engagement portion174. The engagement portion or member 174 may extend away from the body172, for example, in a generally perpendicular direction. The engagementportion 174 may also include a first engagement segment 182 and a secondengagement segment 184. The first and second engagement segments 182,184 may be positioned, for example, parallel to each other to create achannel sized to receive engagement portion 154 and perpendicular to thelong axis of the body 172. The engagement portion 174 may also include aplurality of teeth 176. The plurality of teeth 176 may be positioned,for example, on the interior surfaces of the engagement portion 174. Theplurality of teeth 176 may be positioned on the inner surface of thefirst engagement segment 182 and the inner surface of the secondengagement segment 184. The plurality of teeth 176 may also beconfigured, for example, to engage with the plurality of teeth 156 onthe engagement portion 154 of the third member 150. The body 172 mayalso include a protrusion 178 that extends away from an interior surface175 of body 172. The protrusion 178 is oriented in a relativelyperpendicular direction and may extend from the first side to the secondside of the interior surface 175 near the top of the body 172. Theprotrusion 178 may be, for example, shaped and sized to engage the slot118 in the first member 110 or the slot 138 in the third member 130. Thefourth member 170 may also include at least one engagement protrusion orprotuberance 180 on the interior surface 175 of the body 172. The atleast one engagement protrusion 180 may be positioned on the interiorsurface 175 of the body 172, for example, as shown in FIGS. 5 and 6, theat least one engagement protrusion 180 is positioned below theengagement portion 174 and toward the end of the body 172 and isconfigured similar to engagement protrusions 120, 140, 160. The at leastone engagement protrusion may be, for example, spikes, ridges,serrations, teeth, and other forms of coatings or textures that producea rough surface for engaging with a spinous process to secure the fourthmember 170 to the spinous process.

An insertion instrument or insertion tool 300 is shown in FIGS. 7-9 and11-12. The insertion instrument 300 may include a first member 302 and asecond member 304. The first member 302 and second member 304 may bemoveably coupled together at a pivot point 306. In addition, the firstmember 302 and second member 304 may each include a handle portion 308at a first end and an engagement portion 310 at a second end. Theengagement portions 310 may include a body 312 with a first groove 314and a second groove 316. The first groove 314 and the second groove 316may be positioned on the bottom surfaces of the engagement portions 310.The first groove 314 may be positioned, for example, along thelongitudinal axis of the engagement portion 310 and the second groove316 may extend from the medial surface of the engagement portion 310 toengage the first groove 314. The second groove 316 may be, for example,generally perpendicular to the first groove 314.

As shown in FIGS. 8-9, the insertion instrument 300 may engage the firstattachment portion 190 for insertion into a patient. A first engagementportion 310 of the insertion instrument 300 may engage a portion of thebody 112 and the engagement portion 114 of the first member 110 and asecond engagement portion 310 of the insertion instrument 300 may engagea portion of the body 132 and the engagement portion 134 of the secondmember 130. The body 310 of the second member 304 of the insertioninstrument 300 may engage the first member 110 by, for example, couplingthe first groove 314 to a portion of the body 112 and the second groove316 to a portion of the engagement portion 114 on the first end of thefirst member 110. The body 310 of the first member 302 of the insertioninstrument 300 may engage the second member 130 by, for example,coupling the first groove 314 to a portion of the body 132 and thesecond groove 316 to a portion of the engagement portion 134 on thefirst end of the second member 130. The first member 110 and secondmember 130 may be coupled to the insertion instrument 300 in an openposition as shown in FIG. 8 and then once inserted into the patient thefirst member 110 and second member 130 may be moved to a closedposition, as shown in FIG. 9. As shown in FIG. 10 and described ingreater detail below with reference to FIG. 15, when the first member110 and second member 130 are moved to a closed position, they form thefirst attachment portion 190 and may be coupled to, for example, thespinous process 104 of the patient's first vertebrae 102.

As shown in FIGS. 11-12 the insertion instrument 300 may also engage thesecond attachment portion 192 for insertion into a patient and couplingwith the first attachment portion 190. The insertion instrument 300 maybe coupled to the third member 150 of the second attachment portion 192by, for example, engaging the first groove 314 of the engagement portion310 of the second member 304 with the body 152 of the third member 150.In addition, the second groove 316 of the engagement portion 310 of thesecond member 304 is engaged with the engagement portion 154 of thethird member 150. The insertion instrument 300 is also coupled to thefourth member 170 by, for example, engaging the first groove 314 of theengagement portion 310 of the first member 302 with the body 172 of thefourth member 170. In addition, the second groove 316 of the engagementportion 310 of the first member 302 is engaged with the engagementportion 174 of the fourth member 170. As shown in FIG. 11, the thirdmember 150 and fourth member 170 may be coupled to the insertioninstrument 300 in, for example, an open position for insertion into thepatient. Once inserted into the patient, the third member 150 and fourthmember 170 may be moved to a closed position, as shown in FIG. 12. Whenthe third member 150 and fourth member 170 are moved to a closedposition, the second attachment portion 192 is formed and secured to thefirst attachment portion 190 and the spinous process 108 of thepatient's second vertebrae 106, as shown in FIGS. 13-14 and described ingreater detail below with reference to FIG. 15.

A method for assembling the spinous process fixation device 100 is shownin FIGS. 8-9 and 11-12. The method may include, for instance, obtaininga first member 110 and a second member 130 of the device 100. The methodmay also include coupling the first member 110 and second member 130 toan instrument 300 and activating the instrument 300 to secure the firstmember 110 and second member 130 together. The instrument 300 may thenbe removed from the first member 110 and second member 130. Next, themethod may include obtaining a third member 150 and fourth member 170 ofthe device 100. The third member 150 and fourth member 170 may then besecured to the instrument 300. The method may also include aligning thethird and fourth members 150, 170 with the coupled first and secondmembers 110, 130. The instrument 300 may then be activated to secure thethird member 150 to the fourth member 170 and to also couple the thirdand fourth members 150, 170 to the coupled first and second members 110,130. Once the four members 110, 130, 150, 170 are secured together theinstrument 300 may be removed from the third and fourth members 150, 170leaving assembled device 100.

A method of using the spinous process fixation device 100 in accordancewith one or more aspects of the present invention is shown in FIG. 15.The method for using the minimally invasive device 100 may include, forinstance: placing an incision over the patient's spine 200; obtaining afirst member and second member of the spinous process fixation device202; engaging the first and second members with an insertion tool 204;inserting the insertion tool with the first and second members throughthe incision 206; aligning the first and second members with a firstinterspinous process 208; activating the insertion tool to secure thefirst and second members to the first interspinous process 210;disengaging the insertion tool from the first and second members andremoving the insertion tool from the patient 212; obtaining a thirdmember and a fourth member of the spinous process fixation device 214;engaging the third member and fourth member with the insertion tool 216;inserting and aligning the insertion tool with the attached third andfourth members with the second interspinous process 218; activating theinsertion tool to secure the third and fourth members to the secondinterspinous process and the first and second members 202; and removingthe insertion tool and closing the patient's incision 222.

The method of using the spinous process fixation device 100, shown inFIG. 15, may be described in greater detail with reference to FIGS. 8-14and also includes making an incision over two adjacent spinous processes104, 108 of two vertebrae 102, 106. A dilator (not shown), such as anexpandable dilator, may be inserted into the incision and over the twoadjacent aspects of the spinous processes 104, 108. If an expandabledilator is used it may then be expanded to enable access to the spinousprocesses 104, 108. Alternatively, progressively larger dilators may beinserted over the first dilator to increase the size of the opening andenable access to the spinous processes 104, 108. Once the spinousprocesses 104, 108 are accessible, they may be prepared for fixation ofthe device 100. The spinous processes 104, 108 may be prepared by, forexample, clearing soft tissue from the spinous processes 104, 108.

The method may further include obtaining a first member 110 and a secondmember 130 of the device 100 for insertion into a patient. The firstmember 110 and second member 130 may be secured to an insertioninstrument, for example, insertion instrument 300, as shown in FIG. 8and described in greater detail above. Then, the attached first member110 and second member 130 may be inserted through the incision into thepatient and aligned with the first spinous process 104. The firstspinous process 104 may be, for example, the cephalad spinous process,although it is also contemplated that first member 110 and second member130 may be aligned with and secured to the caudal spinous process. Asdepicted in FIG. 10, the first member 110 and second member 130 may thenbe attached to the cephalad spinous process 104 by, for example,activating the insertion instrument 300 to close the first member 110and second member 130 onto the first spinous process 104 to form a firstattachment portion 190. Once the first member 110 and second member 130have been secured to the first spinous process 104, the insertioninstrument 300 may be removed from the patient.

Next, as shown in FIG. 11, the method may include obtaining a thirdmember 150 and fourth member 170 of the device 100 for insertion intothe patient. The third member 150 and fourth member 170 may be securedto an insertion instrument, for example, insertion instrument 300 asdescribed in greater detail above with reference to FIG. 11. Then theattached third member 150 and fourth member 170 may be inserted throughthe incision into the patient and aligned with the second spinousprocess 108 and the first attachment portion 190. The second spinousprocess 108 may be, for example, the caudal spinous process, although itis also contemplated that the third member 150 and fourth member 170 maybe aligned and attached to the cephalad spinous process. As depicted inFIGS. 13-14, the third member 150 and fourth member 170 may then beattached to the caudal spinous process 108 and may engage the firstattachment portion 190 by, for example, activating the insertioninstrument 300 to close or engage the third member 150 and fourth member170 with the second spinous process 108 to form the second attachmentportion 192. By activating the insertion instrument 300, the third andfourth members 150, 170 also engage the first attachment portion 190 tocomplete the assembly of the device 100. The protrusions 158, 178 of thethird and fourth members 150, 170, respectively, engage the slots 118,138 of the first and second members 110, 130, respectively, to securethe first attachment portion 190 to the second attachment portion 192.

In another embodiment of the method of use, it is also contemplated thatthe first and second members 110, 130 may be positioned with respect tothe first spinous process 104 with the insertion instrument 300 removedprior to securing the first and second members 110, 130 to the firstspinous process 104. Next, the third and fourth members 150, 170 may beinserted with the insertion instrument 300 and aligned with respect tothe second spinous process 108 and the first and second members 110,130. Once proper alignment of the third and fourth members 150, 170 isachieved, the insertion instrument 300 may be activated to move thethird and fourth members 150, 170 to engage the first and second members110, 130. Once the members 110, 130, 150, 170 are all engaged together,the surgeon may then confirm proper alignment with the spinous processes104, 108 and then simultaneously secure both the first and secondmembers 110, 130 and the third and fourth members 150, 170 to the firstand second spinous processes 104, 108, respectively. In addition, as theinsertion instrument 300 is activated the third and fourth members 150,170 engage the first and second members 110, 130 to assemble the device100.

When the first and second attachment portions 190, 192 are secured tothe spinous processes 104, 108, the insertion instrument 300 may bedisengaged from the third and fourth members 150, 170 and removed fromthe patient's incision. As shown in FIGS. 13-14, the device 100 issecured to the spinous processes 104, 108 and the insertion instrument300 has been removed, so the patient's incision may now be closed.

An alternative embodiment of an interspinous process device 400 is shownin FIGS. 16-19. The device 400 may include a body 402 with a first pairof moveable members 420, 420′ and a second pair of moveable members 430,430′. The body 402 may be, for example, curved along the longitudinalaxis, such that the body 402 curves in an anterior direction from acentral portion toward each end. The curve of the body 402 may be, forexample, designed to mimic the shape of the patient's spine. As shown inFIG. 18, the body 402 may include, for example, a plurality of slots404, a plurality of first openings 406 engaging the slots 404, and aplurality of second openings 408 opposite the first openings 406 andalso engaging the slots 404. The plurality of slots 404 may include, forexample, a first set of slots 404 on a first side of the body and asecond set of slots 404 on a second side of the body opposite the firstside. The body 402 may also include at least two cavities 412, 412′extending into the body 402 and engaging at least a portion of theplurality of slots 404. The plurality of slots 404 may be positioned,for example, near the center of the body 402 on the superior andinferior surfaces of the body 402. The device 400 may also include aplurality of pins 410 which may be, for example, sized to pass throughthe first openings 406, pass through the slots 404, and fit into thesecond openings 408.

As shown in FIGS. 16-19, the first pair of moveable members 420, 420′may each include at least one engagement mechanism 422 on the surface ofthe moveable members 420, 420′ that engages a spinous process 108. Theat least one engagement mechanism 422 may be, for example, spikes,ridges, serrations, teeth, and other forms of coatings or textures thatproduce a rough surface for engaging with the spinous process 108 tosecure the moveable members 420, 420′ to the spinous process 108. Thefirst pair of moveable members 420, 420′ may also include a couplingmechanism with a boss 428, a pin 410, and the slots 404. The boss 428 ison a first end of the moveable members 420, 420′ shaped to be receivedwithin the slots 404. The first pair of moveable members 420, 420′ mayalso include an opening 426 through the boss 428 that is shaped toreceive the pin 410. The pin 410 may allow for pivoting movement of thecoupling mechanism to allow for the moveable members 420, 420′ to pivotrelative to the body 402. The securement mechanism is shown as a pin 410in FIGS. 16-19, but it may also include, for example, a set of detents,a knob, or any other mechanism allowing for pivoting of the moveablemembers 420, 420′. The boss 428 of the coupling mechanism may be shapedto allow for pivoting movement, for example, the boss 428 may be curvedor cylindrical like. The moveable members 420, 420′ may also eachinclude a movement mechanism 424, 424′ positioned on a top or bottomsurface of the bosses 428. Alternatively, the movement mechanism 424,424′ may be positioned intermediate the bosses 428 between the first endand the second end of the bosses 428. The movement mechanism 424, 424′may include, for example, teeth, grooves, or gears (not shown)configured to engage an instrument 440 and corresponding worm gears 446,448, described in greater detail below, to deploy the moveable members420, 420′. When the moveable members 420, 420′ are deployed they mayengage a spinous process 108, as shown in FIG. 19.

The second pair of moveable members 430, 430′, as shown in FIGS. 17-19,may each include at least one engagement mechanism 432 on the surface ofthe moveable members 430, 430′ that engages a spinous process 104. Theat least one engagement mechanism 432 is configured similar toengagement mechanism 422 for engaging with the spinous process 104 tosecure the moveable members 430, 430′ to the spinous process 104. Thesecond pair of moveable members 430, 430′ may also include a boss 438 ona first end of the moveable members 430, 430′ shaped to be receivedwithin the slots 404. The second pair of moveable members 430, 430′ mayalso include an opening 436, a pin 410, and a movement mechanism 434 asdescribed above with reference to moveable members 420, 420′. Themoveable members 430, 430′ may be deployed to engage spinous process104, as shown in FIG. 19.

As shown in FIGS. 16 and 18, the device 400 may also include at leastone worm gear mechanism 440 which may be positioned in the cavities 412,412′. The at least one worm gear mechanism 440 may be permanentlyintegrated inside the cavities 412, 412′ or alternatively, the at leastone worm gear mechanism 440 may be removable from the cavities 412,412′. In one embodiment, a worm gear mechanism 440 is moveably securedin each of the cavities 412, 412′. The worm gear mechanism 440 mayinclude a shaft 442 with a coupling tip 444 for rotatably coupling tothe body 402 inside one of the cavities 412, 412′, a first worm gear446, and a second worm gear 448. The first worm gear 446 may be, forexample, a right hand worm gear, and the second worm gear 448 may be,for example, a left hand worm gear. Although alternative arrangementsfor the first and second worm gears 446, 448 are also contemplatedincluding, but not limited to, gear 446 being a left hand gear and gear448 being a right hand gear, both gears 446, 448 being left hand gears,or both gears 446, 448 being right hand gears. The worm gear mechanism440 may also have an engagement opening 450 in the shaft 442 on the endopposite the coupling tip 444. The opening 450 may receive a tool, forexample, a screwdriver or drill, to rotate the worm gear mechanism 440.The opening 450 may be, for example, a hex opening as shown in FIG. 24,although alternative shapes for the opening 450 are also contemplated.

When inserted into a cavity 412, the coupling tip 444 may sit in acorresponding opening (not shown) positioned past the slot 404 thatengages the moveable member 420′. This enables the first worm gear 446to align and couple with the movement mechanism 424′ and the second wormgear 448 to align and couple with the movement mechanism 424 to allowfor rotation of the worm gear mechanism 440 to in turn rotate themovement mechanisms 424′, 424 to deploy or retract the moveable members420, 420′, as described in greater detail below. When the worm gearmechanism 440 is inserted into cavity 412′, the first and second wormgears 446, 448 will align and couple with the movement mechanisms 434′,434, respectively, as described above with reference to cavity 412,which will not be discussed here for brevity sake. Although theadjustment mechanism is shown as a worm gear mechanism 440 in thedepicted embodiments, it may also include a spiral thread, rack andpinion, or other alternative mechanism that align with the movementmechanisms 424′, 424, 434′, 434 to deploy or retract the moveablemembers 420′, 420, 430′, 430.

The worm gear mechanism 440 may be inset within the cavities 412, 412′to allow for insertion of a locking mechanism 460, as seen in FIG. 25,into each of the cavities 412, 412′. The worm gear mechanism 440 may beinset to allow for the locking mechanism 460 to be inserted flush withthe body 402 of the device 400. The locking mechanism 460 may include astem portion 462 and a head portion 464. The stem portion 462 may besized to engage the opening 450 of the worm gear mechanism 440. The stemportion 462 may be, for example, slightly smaller than the opening 450to allow the stem portion 462 to bottom out and prevent the worm gearmechanism 440 from moving after insertion of the locking mechanism 460.The head portion 464 may be sized to engage the cavities 412, 412′ ofthe device 400. To secure the locking mechanism 460 in the body 402, thehead portion 464 may be, for example, threaded to engage correspondingthreads in the cavities 412, 412′. Alternatively, the head portion 464may have another means for securing the locking mechanism 460 to thebody 402, as known by one of skill in the art, for example, at least oneprotrusion on the surface of the head portion 464 to engage a lip (notshown) in the opening of the cavities 412, 412′.

In another embodiment of the interspinous process device 400, the atleast two cavities may be positioned on opposite ends of the body 402. Afirst cavity (not shown) may be positioned on a first end and engage atleast a portion of two of the slots 404, for example, the slots 404 thatreceive the moveable members 420, 430. The second cavity (not shown) maybe positioned on a second end and engage at least a portion of two ofthe slots 404, for example, the slots 404 that receive the moveablemembers 420′, 430′. An alternative embodiment of the at least one wormgear mechanism 440 may be inserted into the first cavity to engage themovement mechanisms 424, 434 of the moveable members 420, 430. As theworm gear mechanism 440 is rotated, the worm gear mechanism 440 engagesthe movement mechanisms 424, 434 to deploy the moveable members 420,430. The movement mechanisms 424, 434 may be positioned on the bosses428, 438 to allow for the moveable members 420, 430 to be deployedsimultaneously as the worm gear mechanism 440 is rotated within thefirst cavity. The worm gear mechanism 440 may be inserted into thesecond cavity to engage the movement mechanisms 424′, 434′ of themoveable members 420′, 430′. As the worm gear mechanism 440 is rotated,the worm gear mechanism 440 engages the movement mechanisms 424′, 434′to deploy the moveable members 420′, 430′. The movement mechanisms 424′,434′ may be positioned on the bosses 428, 438 to allow for the moveablemembers 420′, 430′ to be deployed simultaneously as the worm gearmechanism 440 is rotated within the second cavity.

In yet another embodiment of the interspinous process device 400, thebody 402 may include one cavity positioned on a first end and extendingalong the longitudinal axis of the body 402, engaging at least a portionof each slot 404. Another alternative embodiment of the worm gearmechanism 440 may be inserted into the cavity to engage the movementmechanisms 424, 434 of the moveable members 420, 430. The worm gearmechanism 440 may then be rotated, engaging and rotating the movementmechanisms 424, 434 to deploy the moveable members 420, 430. The wormgear mechanism 440 may then be moved to engage the movement mechanisms424′, 434′ of the moveable members 420′, 430′. The worm gear mechanism440 may then be rotated, engaging and rotating the movement mechanisms424′, 434′ to deploy the moveable members 420′, 430′. The movementmechanisms 424, 434 may be positioned on the bosses 428, 438 to allowfor the moveable members 420, 430 to be deployed simultaneously as theworm gear mechanism 440 is rotated within the cavity. The movementmechanisms 424′, 434′ may be positioned on the bosses 428, 438 to allowfor the moveable members 420′, 430′ to be deployed simultaneously as theworm gear mechanism 440 is rotated within the cavity.

Another embodiment of an interspinous process device 500 is shown inFIGS. 20-23. The interspinous process device 500 may include a body 502,a first pair of moveable members 520, 520′, and a second pair ofmoveable members 530, 530′. The body 502 may have, for example, agenerally rectangular shape, however other cross-sectional geometriesmay be used. As shown in FIG. 22, the body 502 may include, for example,a plurality of slots 504. The plurality of slots 504 may include a firstset of slots 504 on a first side of the body 502 and a second set ofslots 504 (not shown) on a second side of the body 502 opposite thefirst side. The first side of the body 502 may be, for example, aninferior side and the second side of the body 502 may be, for example, asuperior side. The plurality of slots 504 may be positioned, forexample, near the center of the body 502. The body 502 may furtherinclude a plurality of first openings 506 engaging the slots 504 and,for example, extending from a front side of the body 502 or a posteriorside of the patient into the slot 504. In addition, the body 502 mayinclude a plurality of second openings 508 engaging the slots 504 and,for example, extending from the slot 504 toward a back side of the body502 of an anterior side of the patient. The plurality of second openings508 may, for example, only extend partially into the body 502 and maynot be through holes such as the plurality of first openings 506. Asshown in FIGS. 20-23, the body 502 may also include at least twocavities 512, 512′. The cavities 512, 512′, may extend into the body 502and may engage at least a portion of the plurality of slots 504. Thedevice 500 may also include a plurality of pins 510 which may be sizedto pass through the first openings 506, through the slots 504, andengage the second openings 508.

The first pair of moveable members 520, 520′ are shown in FIGS. 20-23.The first pair of moveable members 520, 520′ may each include at leastone engagement mechanism 522 on the surface that engages the spinousprocess 108. The at least one engagement mechanism 522 may be, forexample, spikes, ridges, serrations, teeth, and other forms of coatingsor textures that produce a rough surface for engaging with the spinousprocess 108 to assist with securing the moveable members 520, 520′ tothe spinous process 108. The moveable members 520, 520′ may also includea boss 528 on a first end and an opening 526 extending through the boss528 from the top surface to the bottom surface. The bosses 528 may be,for example, sized and shaped to be received within the slots 504 andmay be, for example, relatively cylindrical to allow for the moveablemembers 520, 520′ to pivotally move relative to the body 502. Theopenings 526 may be, for example, shaped and sized to receive a pin 510.The pin 510 may be used to secure the moveable members 520, 520′ to thebody 502 while allowing for the moveable members 520, 520′ to rotaterelative to the body 502 between an open and a closed position. Themoveable members 520, 520′ may also each include a movement mechanism524, 524′ positioned, for example, on a top or bottom surface of thecylindrical bosses 528. Alternatively, the movement mechanism 524, 524′may be positioned intermediate the bosses 528 between the first end andthe second end of the bosses 528. The movement mechanism 524, 524′ mayinclude, for example, teeth, grooves, or gears (not shown) to engage aninstrument, such as, the worm gear mechanism 440, as described ingreater detail below, to deploy the moveable members 520, 520′ from aretracted state to a deployed state. The first worm gear 446 of the wormgear mechanism 440 may couple to the movement mechanisms 524′ and thesecond worm gear 448 may couple to the movement mechanisms 524. Then asthe worm gear mechanism 440 is rotated the first and second worm gears446, 448 rotate engaging the movement mechanisms 524′, 524 to deploy orretract the moveable members 520′, 520. When the moveable members 520,520′ are deployed, they may engage, for example, a spinous process 108,as shown in FIG. 23.

As shown in FIGS. 21-23, the second pair of moveable members 530, 530′may include at least one engagement mechanism 532 on the surface of themoveable members 530, 530′ that engages a spinous process 104. The atleast one engagement mechanism 532 may be of the type described abovewith reference to engagement mechanism 522 and will not be discussedagain here for brevity sake. The moveable members 530, 530′ may alsoinclude a boss 538 and an opening 536 of the type described above withreference to boss 528 and opening 526. Pins 510 may be used to securethe moveable members 530, 530′ to the body 502 while allowing for themoveable members 530, 530′ to rotate relative to the body 502 from anopen to a closed position. The moveable members 530, 530′ may also eachinclude a movement mechanism 534, 534′ of the type described above withreference to movement mechanisms 524, 524′. The movement mechanisms 534,534′ may engage an instrument, such as, worm gear mechanism 440, asdescribed in greater detail below, to deploy the moveable members 530,530′. The first worm gear 446 of the worm gear mechanism 440 may coupleto the movement mechanisms 534′ and the second worm gear 448 may coupleto the movement mechanisms 534. Then as the worm gear mechanism 440 isrotated the first and second worm gears 446, 448 rotate engaging themovement mechanisms 534′, 534 to deploy or retract the moveable members530′, 530. When the moveable members 530, 530′ are deployed, they mayengage, for example, a spinous process 104, as shown in FIG. 23.

As shown in FIG. 22, the device 500 may also include at least one wormgear mechanism 440 which may be inserted into the cavities 512, 512′.The at least one worm gear mechanism 440 is as described above withreference to device 400 and will not be described again here for brevitysake. In addition, device 500 may also include at least one lockingmechanism 460, as described in greater detail above, to secure the atleast one worm gear mechanism 440 in the desired position.

In another embodiment of the interspinous process device 500, the atleast two cavities may be positioned on opposite ends of the body 502. Afirst cavity (not shown) may be positioned on a first end and engage atleast a portion of two of the slots 504, for example, the slots 504 thatreceive the moveable members 520, 530. The second cavity (not shown) maybe positioned on a second end and engage at least a portion of two ofthe slots 504, for example, the slots 504 that receive the moveablemembers 520′, 530′. An alternative embodiment of the at least one wormgear mechanism 440 may be inserted into the first cavity to engage themovement mechanisms 524, 534 of the moveable members 520, 530. As theworm gear mechanism 440 is rotated, the worm gear mechanism 440 engagesthe movement mechanisms 524, 534 to deploy the moveable members 520,530. The movement mechanisms 524, 534 may be positioned on the bosses528, 538 to allow for the moveable members 520, 530 to be deployedsimultaneously as the worm gear mechanism 440 is rotated within thefirst cavity. The worm gear mechanism 440 may be inserted into thesecond cavity to engage the movement mechanisms 524′, 534′ of themoveable members 520′, 530′. As the worm gear mechanism 440 is rotated,the worm gear mechanism 440 engages the movement mechanisms 524′, 534′to deploy the moveable members 520′, 530′. The movement mechanisms 524′,534′ may be positioned on the bosses 528, 538 to allow for the moveablemembers 520′, 530′ to be deployed simultaneously as the worm gearmechanism 440 is rotated within the second cavity.

In yet another embodiment of the interspinous process device 500, thebody 502 may include one cavity positioned on a first end and extendingalong the longitudinal axis of the body 502, engaging at least a portionof each slot 504. Another alternative embodiment of the worm gearmechanism 440 may be inserted into the cavity to engage the movementmechanisms 524, 534 of the moveable members 520, 530. The worm gearmechanism 440 may then be rotated, engaging and rotating the movementmechanisms 524, 534 to deploy the moveable members 520, 530. The wormgear mechanism 440 may then be moved to engage the movement mechanisms524′, 534′ of the moveable members 520′, 530′. The worm gear mechanism440 may then be rotated, engaging and rotating the movement mechanisms524′, 534′ to deploy the moveable members 520′, 530′. The movementmechanisms 524, 534 may be positioned on the bosses 528, 538 to allowfor the moveable members 520, 530 to be deployed simultaneously as theworm gear mechanism 440 is rotated within the cavity. The movementmechanisms 524′, 534′ may be positioned on the bosses 528, 538 to allowfor the moveable members 520′, 530′ to be deployed simultaneously as theworm gear mechanism 440 is rotated within the cavity.

A method of using the spinous process devices 400, 500 in accordancewith one or more aspects of the present invention is shown in FIG. 26.The method for using the spinous process devices 400, 500 may include,for instance: placing an incision over a patient's spine 600. The methodmay also include obtaining an interspinous process device 602 andpreparing the patient's spine for insertion of the interspinous processdevice 604. The method may further include inserting the interspinousprocess device into the patient's spine with an insertion device 606 andaligning the interspinous process device between two adjacent spinousprocesses 608. In addition, the method may include using an instrumentto engage a worm gear mechanism in a first cavity of the interspinousprocess device 610 and deploying a first set of moveable members toengage a first spinous process 612. The method may also include removingand using the instrument to engage a worm gear mechanism in a secondcavity of the interspinous process device 614 and deploying a second setof moveable members to engage a second spinous process 616. The methodmay further include removing the instrument from the patient 618.Finally, the method may include completing the surgical procedure andclosing the patient 620.

The method of using the spinous process devices 400, 500, as shown inFIG. 26, is described here in greater detail and also includes placingan incision over two spinous processes 104, 108 of a patient's spine.The incision may be positioned to allow for insertion, for example,posterolateral to the midline of the spine or obliquely. Then a dilator(not shown) may be inserted into the incision to access the interspinousprocess space between the two spinous processes 104, 108. The dilatorsmay be, for example, an expandable dilator or a series of dilators, andthey may be straight or curved. Next a reamer instrument, for example,reamer instrument 700 may be inserted to prepare the space for insertionof a spinous process device 400, 500. After the patient's spine isprepared, the spinous process device 400, 500 may be coupled to aninsertion device for placement between two spinous processes 104, 108.Once a desired position of the device 400, 500 is achieved, then themoveable members 420, 420′, 430, 430′, 520, 520′, 530 may be deployed toengage the spinous processes 104, 105.

The moveable members 420, 420′, 430, 430′, 520, 520′, 530, 530′ may bedeployed, for example, by inserting an instrument into the cavities 412,412′, 512, 512′ to engage the engagement opening 450 of a worm gearmechanism 440. The instrument may be, for example, a screw driver ordrill. For example, the instrument may be inserted into a first cavity412 to engage the engagement opening 450, then the instrument may berotated in a first direction to rotate the worm gear mechanism 440. Asthe worm gear mechanism 440 rotates, the first worm gear 446 and secondworm gear 448 also rotate. Since the first and second worm gears 446,448 are positioned to engage the movement mechanisms 424′, 424,respectively, as the worm gears 446, 448 rotate, the aligned movementmechanisms 424′, 424 also rotate to deploy the moveable members 420,420′.

Next, the instrument may be removed from the first cavity 412 andinserted into a second cavity 412′ to engage the engagement opening 450of the worm gear mechanism 440 in the second cavity 412′. The instrumentmay be rotated in a first direction to turn the worm gear mechanism 400.As described in greater detail above, as the worm gear mechanism 440 isrotated the first and second worm gears 446, 448 rotate and in turnrotate the movement mechanisms 434′, 434, respectively to deploy themoveable members 430, 430′. Where both worm gear mechanisms 400 areidentical the direction of rotation may be, for example,counterclockwise or clockwise, for example, in the depicted embodiment,the direction is counterclockwise. In another embodiment, if the wormgear mechanism 400 in the first cavity 412 includes a first left handworm gear 446 and a second right hand worm gear 448 and the worm gearmechanism 400 in the second cavity 412′ includes a first right hand wormgear 446 and a second left hand worm gear 448, then the worm gearmechanism 400 in the first cavity 412 may be rotated clockwise and theworm gear mechanism 400 in the second cavity 412′ may be rotatedcounterclockwise. Alternative mechanisms that accomplish the same orsimilar function may be used in place of worm gear mechanism 440 todeploy the moveable members 420, 420′, 430, 430′.

The moveable members 520, 520′, 530, 530′ of device 500 may also bedeployed as described above with reference to device 400, which will notbe described again here for brevity sake.

After the moveable members are deployed, the instrument may be removedfrom the patient. Then a compression device (not shown) may be used tolock the device 400, 500 to ensure that the device 400, 500 is firmlygrasping the spinous processes 104, 108. Next the insertion device maybe removed from the patient and the surgical procedure may be completed.Finally, the patient's incision may be closed.

A reamer instrument 700 is shown in FIGS. 27-28. The reamer instrument700 may include a first shaft 702 coupled to a second shaft 704 by ajoint 708. The first shaft 702 may include an attachment portion (notshown) on a first end for engagement with a drill and may be coupled tothe joint 708 on the second end. The second shaft 704 may be coupled tothe joint 708 on a first end and may include a reamer portion 706 on thesecond end. The joint 708 may include a first body 710, a second body712, and a hinge member 714 moveably coupling the first body 710 andsecond body 712. The first body 710 may be attached to the second end ofthe first shaft 702 and the second body 712 may be attached to the firstend of the second shaft 704. The hinge member 714 may include a firstpin 716 and a second pin 718 which are coupled together to form thehinge member 714. The first pin 716 may be positioned perpendicular tothe second pin 718. The first pin 716 may engage the first body 710 andthe second pin 718 may engage the second body 712 to enable the secondshaft 704 to be positioned at any angle relative to the first shaft 702as the reamer portion 706 is drilled into a patient's bones.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprise” (andany form of comprise, such as “comprises” and “comprising”), “have” (andany form of have, such as “has”, and “having”), “include” (and any formof include, such as “includes” and “including”), and “contain” (and anyform of contain, such as “contains” and “containing”) are open-endedlinking verbs. As a result, a method or device that “comprises,” “has,”“includes,” or “contains” one or more steps or elements possesses thoseone or more steps or elements, but is not limited to possessing onlythose one or more steps or elements. Likewise, a step of a method or anelement of a device that “comprises,” “has,” “includes,” or “contains”one or more features possesses those one or more features, but is notlimited to possessing only those one or more features. Furthermore, adevice or structure that is configured in a certain way is configured inat least that way, but may also be configured in ways that are notlisted.

The invention has been described with reference to the preferredembodiments. It will be understood that the architectural andoperational embodiments described herein are exemplary of a plurality ofpossible arrangements to provide the same general features,characteristics, and general system operation. Modifications andalterations will occur to others upon a reading and understanding of thepreceding detailed description. It is intended that the invention beconstrued as including all such modifications and alterations.

Having thus described the preferred embodiments, the invention is nowclaimed to be:
 1. A spinous process fixation device, comprising: a firstattachment portion comprising: a first member; and a second memberconfigured to couple to the first member; a second attachment portionengaging the first attachment portion, the second attachment portioncomprising: a third member; and a fourth member configured to couple tothe third member; wherein the first attachment portion and the secondattachment portion are positioned to couple to at least two spinousprocesses; wherein the first member comprises: a body; an engagementmember; a plurality of teeth positioned on the engagement member; and aslot positioned on an exterior surface of the body and extending from afirst side to a second side of the body, wherein the second memberincludes comprises: a body; and an engagement portion, and theengagement member of the first member couples to the engagement portionof the second member; and wherein the third member comprises: a body; anengagement member; and a protrusion extending away from an interiorsurface of the body and extending from a first side to a second side,wherein the protrusion of the third member engages the slot of the firstmember when the first attachment portion couples to the secondattachment portion, wherein the fourth member comprises: a body; and anengagement portion, and wherein the engagement member of the thirdmember couples to the engagement portion of the fourth member.
 2. Thespinous process fixation device of claim 1, wherein the first memberfurther comprises: at least one protuberance on an interior surface ofthe body positioned between a top of the body and the engagement member.3. The spinous process fixation device of claim 2, wherein theengagement portion of the second member comprises: a first engagementsegment; and a second engagement segment positioned parallel to andspaced apart from the first engagement segment to form a channel, thechannel sized to receive the engagement member of the first member; andwherein the second member further comprises: a plurality of first teethpositioned on an inner surface of the first engagement segment in thechannel; a plurality of second teeth positioned on an inner surface ofthe second engagement segment in the channel, wherein the plurality ofteeth on the engagement member of the first member engage the pluralityof first teeth and the plurality of second teeth of the engagementportion of the second member; a slot positioned on an exterior surfaceof the body and extending from a first side to a second side of thebody; and at least one protuberance on an interior surface of the bodypositioned between a top of the body and the engagement portion.
 4. Thespinous process fixation device of claim 3, wherein the third memberfurther comprises: a plurality of teeth positioned on the engagementmember; and at least one protuberance on the interior surface of thebody positioned between the engagement member and a bottom of the body.5. The spinous process fixation device of claim 4, wherein theengagement portion of the fourth member comprises: a first engagementsegment; and a second engagement segment positioned parallel to andspaced apart from the first engagement segment to form a channel,wherein the channel is sized to receive the engagement member of thethird member; and wherein the second member further comprises: aplurality of first teeth positioned on an inner surface of the firstengagement segment in the channel; a plurality of second teethpositioned on an inner surface of the second engagement segment in thechannel, wherein the plurality of teeth on the engagement member of thethird member engage the plurality of first teeth and the plurality ofsecond teeth of the engagement portion of the fourth member; aprotrusion extending away from an interior surface of the body andextending from a first side to a second side; and at least oneprotuberance on the interior surface of the body positioned between theengagement portion and a bottom of the body.
 6. The spinous processfixation device of claim 5, wherein the protrusion of the fourth memberengages the slot of the second member.
 7. The spinous process fixationdevice of claim 1, wherein the engagement member is angled relative tothe body.
 8. The spinous process fixation device of claim 1, wherein theengagement member extends normal to the interior surface of the body. 9.The spinous process fixation device of claim 1, wherein the engagementportion is angled relative to the body.
 10. The spinous process fixationdevice of claim 3, wherein the engagement portion is normal to theinterior surface of the body.
 11. A spinous process fixation system,comprising: a spinous process fixation device comprising: a firstattachment portion comprising: a first member; and a second memberconfigured to couple to the first member; a second attachment portionengaging the first attachment portion, the second attachment portioncomprising: a third member; and a fourth member configured to couple tothe third member; wherein the first attachment portion and the secondattachment portion are positioned to couple at least two spinousprocesses; and an insertion instrument configured for engagement withthe spinous process fixation device, wherein the insertion instrumentcomprises: a first member with a handle portion and an engagementportion; a second member with a handle portion and an engagementportion; and a pivot point moveably coupling the first member and thesecond member; wherein the engagement portion of the first membercomprises: a body; a first groove extending along a longitudinal axis ofa bottom surface of the body; and a second groove extendingperpendicular to the first groove from a medial side of the body tointersect the first groove; wherein the engagement portion of the secondmember comprises: a body; a first groove extending along a longitudinalaxis of a bottom surface of the body; and a second groove extendingperpendicular to the first groove from a medial side of the body tointersect the first groove.
 12. The spinous process fixation system ofclaim 11, wherein the first groove of the first member of the insertioninstrument engages the body of the first member of the spinous processfixation device, the second groove of the first member of the insertioninstrument engages the engagement member of the first member of thespinous process fixation device, the first groove of the second memberof the insertion instrument engages the body of the second member of thespinous process fixation device, and the second groove of the secondmember of the insertion instrument engages the engagement portion of thesecond member of the spinous process fixation device.
 13. The spinousprocess fixation system of claim 11, wherein the first groove of thefirst member of the insertion instrument engages the body of the thirdmember of the spinous process fixation device, the second groove of thefirst member of the insertion instrument engages the engagement memberof the third member of the spinous process fixation device, the firstgroove of the second member of the insertion instrument engages the bodyof the fourth member of the spinous process fixation device, and thesecond groove of the second member of the insertion instrument engagesthe engagement portion of the fourth member of the spinous processfixation device.
 14. A spinous process fixation assembly, comprising: afirst member having an engagement member coupled to and extending awayfrom an interior surface of the first member; a second member having anengagement portion coupled to and extending away from an interiorsurface of the second member; a third member having an engagement membercoupled to and extending away from an interior surface of the thirdmember; and a fourth member having an engagement portion coupled to andextending away from an interior surface of the fourth member; whereinthe engagement member of the first member connects to the engagementportion of the second member and the engagement member of the thirdmember connects to the engagement portion of the fourth member to form aspinous process fixation assembly; wherein the interior surface of thethird member engages an exterior surface of the first member and theinterior surface of the fourth member engages an exterior surface of thesecond member to form the spinous process fixation assembly.
 15. Thespinous process fixation assembly of claim 14, further comprising afirst attachment portion comprising the first member connected to thesecond member, wherein the first member is positioned parallel to thesecond member when assembled.
 16. The spinous process fixation assemblyof claim 14, further comprising a second attachment portion comprisingthe third member connected to the fourth member, wherein the thirdmember is positioned parallel to the fourth member when assembled.